As car safety progresses, an increased awareness for passenger safety is being perceived with resulting innovations in many areas. One of these innovations is the installation of seat belts having a waist/shoulder strap in the rear seats of new cars in addition to the standard installation in the front seats. Upon first impression, this appears to be a logical safety improvement and for most adults this is the case, however, for passengers of a reduced height, especially children, it is a potential for serious injury.
For children under the height of 95 cm, conventional child seats are used to secure the child safely in a vehicle. However, for children between the height of 95 and 155 cm, a child safety seat is too small and the conventional seat belt is ineffective in safely securing the child in the vehicle. It is known in the prior art to provide a shoulder belt adjuster for the purposes of reducing the height of the shoulder strap anchor point to a height which more suitably fits the reduced height passenger.
In U.S. Pat. No. 4,799,737 an auxiliary adjusting device for the shoulder strap of a seat belt is described, the device being mounted to a side wall of the vehicle at a given reduced height and having a yoke for guiding the shoulder strap through the device. In U.S. Pat. No. 4,796,919, a clamp device is disclosed for clamping the diagonal run of the shoulder belt to the vertical run of the shoulder belt to reduce the height of the diagonal run. In U.S. Pat. No. 4,938,535, an adjustable shoulder/lap seat belt adaptor is described in which a strap secured at one end to the lap belt is wrapped around and fastened to the shoulder strap while maintaining the shoulder strap at a lowered position in order to accommodate a reduced height passenger. In U.S. Pat. No. 4,946,198, a similar adaptor has a safety strap clipped between a shoulder belt fastener and a lap belt fastener. U.S. Pat. No. 4,832,367 describes a front mount shoulder belt relocation device having an auxiliary strap extending vertically between and interconnecting the lap belt and a medial portion of the shoulder belt. Published PCT application WO 88/04622 describes a slotted triangular plate for interconnecting the lap belt with the medial portion of the shoulder belt.
In the conventional devices, the shoulder belt can be pulled by the child without the device preventing the shoulder belt from being placed by the child under his arms and essentially to a useless position.
Also, in the conventional devices, no device provides an adequate combination of low cost, ease of installation, and efficient operation during normal use and collision.